For those of us like me
who think "I'll remember where the wires go" when removing the alternator,
here's the diagram for the Motorola 51 amp on the M25. prestolite.com/images_alts/dimdraw/pdf_web/8MR2049KA_rear.pdf
Note: B+ and B- is charge terminal and ground terminal , A/C tap is the
signal that drives the Tach, The dangling wire with the plastic disconnect on it
is the exciter wire from the panel. Newer alternators may eliminate this
(self-exciting). B+ terminal is connected to only the regulator wire. Also, the
voltage regulator schematic: prestolite.com/images_alts/wiredia/pdf_web/8MR2049KA_wire_dia.pdf

Replaced the
glow plugs , $60 each from
Torrensen. I used: $8.21 from Tractor Smart (Keller Brothers)
717-450-1250 KB part # 15261-65510 for the Z500-1 engine. NKG # Y103K
starts with 20 second warm up instead of 120 for the 5411from George Goodall -
My hand
book calls for 14.5 to 18.1 foot lbs. Thatís for the D-850 engine ( M-25 ).
I also used NKG Y103K's.

Pump
replacement , I just replaced a Sherwood G908 raw water pump on my
M3-20 engine with an Oberdorfer N202M-16 (1/2" ports) pump. The
cost of the new Orberdorfer pump was < $240 (incl. S& H) from Depco in Florida
(www.depcopump.com or
1-800-446-156). The Oberdorfer pump can use the two 6Mx1 studs that
hold the clips for the Sherwood G908 pump. I ordered a gasket, which
matched the shape of the 5-hole mounting flange, but the circular gasket from
the Sherwood G908 pump fit better, so I reused it (with some gasket pucky).
The Oberdorfer comes in two models -- the -15 has 3/8" NPT ports and the -16 has
1/2" ports -- so you'll want the one with ports that match the elbows in your
old pump (or they'll supply and install new elbows, if you want). I hated the
Sherwood G908 because of the location of the cover screws.

Beta Marine's engine range is based on the most
advanced water-cooled diesels from Kubota. If you are repowering, we have
drop-in replacement engines that provide safer more fuel efficient and reliable
alternatives to the old Universal engines. We offer friendly. experienced
customer service and special discounts to Catalina 30 owners. Jay Kimball,
1.888.792.2382, www.BetaMarineNW.com

An excellent replacement oil filter for the many Universal engines that use the
Universal part # 300209 filter (M3-20, M-25XP, et al) is the AC Delco PF1127
oil filter. The nice thing about the PF1127 is that it is exactly 3" in
diameter, while most of the other replacements are somewhat larger, usually
about 3-1/4". On my M3-20 engine, filters larger than 3" in diameter get
rubbed by the drive belt, which isn't good for the belt or the filter. The
Kubota 70000-15241 oil filter is also 3" (when they don't mislabel it -- I got a
Kubota filter labeled 70000-15241 which was larger than 3" and had the wrong
threads!). In my area, Pep Boys carries the AC Delco filter.Bryant Pratt